package queue;

class MyCircularQueue {

    private int[] elem;
    private int front; //队头
    private int rear;  //队尾

    public MyCircularQueue(int k) {
        this.elem = new int[k + 1];
    }
    
    public boolean enQueue(int value) {
        if(isFull()){
            return false;
        }
        elem[rear] = value;
        rear = (rear + 1) % elem.length;
        return true;
    }
    
    public boolean deQueue() {
        if(isEmpty()){
            return false;
        }
        front = (front + 1) % elem.length;
        return true;
    }
    
    public int Front() {
        if(isEmpty()){
            return -1;
        }
        return elem[front];
    }
    
    public int Rear() {
        if(isEmpty()){
            return -1;
        }
        if(rear == 0){
            return elem[elem.length - 1];
        }else {
            return elem[rear - 1];
        }
    }
    
    public boolean isEmpty() {
        return front == rear;
    }
    
    public boolean isFull() {
        if((rear + 1) % elem.length == front){
            return true;
        }
        return false;
    }
}